The present invention is directed to a memory switch device for a digital memory device. More particularly, the present invention is directed to a memory switch device that includes a transistor with moving gate which can be move electrically to turn the transistor ON or OFF, thereby enabling the storing of information in a more permanent fashion or the storing of information without requiring power to maintain the stored information.
Examples of conventional devices for digitally storing information are dynamic random access memories and disk drive magnetic memories. A dynamic random access memory stores information electrostatically. Moreover, a dynamic random access memory allows a user to dynamically write to a memory device more than one time so that the contents of the memory can be dynamically changed. Since a dynamic random access memory is a volatile memory, supplemental power is needed for the dynamic random access memory to maintain the stored information.
On the other hand, a disk drive magnetic memory stores information magnetically. A disk drive magnetic memory also allows a user to dynamically write to a memory device more than one time so that the contents of the memory can be dynamically changed. However, since a disk drive magnetic memory is a non-volatile memory, the disk drive magnetic memory does not require supplemental power to maintain the stored information.
As noted above, one disadvantage of a dynamic random access memory is that the dynamic random access memory is volatile. Thus, when the electricity or electric power being supplied to the dynamic random access memory is turned OFF, the contents of the memory are lost. Also, although the disk drive magnetic memory is a non-volatile memory, the use of a disk drive magnetic memory can be a power drain due to the need to keep the disk spinning. Thus, it is desirable to provide a non-volatile memory that has the dynamic characteristics of a dynamic random access memory but does not have the power requirements of a disk drive magnetic memory.
Conventionally, a memory device in the form of a micro-mechanical device has been utilized as an alternative memory to a dynamic random access memory or a disk drive magnetic memory. These conventional micro-mechanical devices are electrical switches which can be fabricated on a semiconductor substrate such as silicon. More specifically, the conventional micro-mechanical device may include a flexible mechanical component under mechanical stress, which has two stable positions.
In the conventional micro-mechanical device, a transition of the mechanical component from one stable position to another stable position can be obtained by overcoming the mechanical spring force in the mechanical component. The mechanical bi-stable operation can be utilized for storing digital electronic signals and information in general. The logic state “0” can be assigned to one of the two stable positions of the mechanical component, and the logic state “1” can be assigned to the other of the two stable positions. The actual determination of the position of the mechanical component can be realized by measuring the capacitance of a capacitor which has the mechanical component formed as one of the capacitor's plates.
A disadvantage of this conventional micro-mechanical device is the need for a separate circuit to measure a capacitance so as to determine the mechanical position and then generate the appropriate voltage to represent the logic state. This additional circuitry slows down the operations of the memory.
Therefore, it is desirable to provide a non-volatile memory that has the dynamic characteristics of a dynamic random access memory but does not have the power requirements of a disk drive magnetic memory. Moreover, it is desirable to provide a non-volatile memory that has a mechanical component which does not negatively impact the speed of the operations of the memory.
A mechanical memory transistor includes a substrate having formed thereon a source region and a drain region; an oxide formed upon a portion of the source region and upon a portion of the drain region; a pull up electrode positioned above such that a gap is formed between the pull up electrode and the substrate; and a movable gate having a first position and a second position, the movable gate being located in the gap between the pull up electrode and the substrate. The movable gate is in contact with the pull up electrode when the movable gate is in the first position, and the movable gate is in contact with the oxide to form a gate region when the movable gate is in the second position. The movable gate, in conjunction with the source region and the drain region and when the movable gate is in the second position, forms a transistor.
A mechanical memory element includes a transistor. The transistor has a substrate having formed thereon a source region and a drain region, an oxide formed upon a portion of the source region and upon a portion of the drain region, a pull up electrode positioned above such that a gap is formed between the pull up electrode and the substrate, and a movable gate having a first position and a second position, the movable gate being located in the gap between the pull up electrode and the substrate, the movable gate being in contact with the pull up electrode when the movable gate is in the first position, the movable gate being in contact with the oxide to form a gate region when the movable gate is in the second position. The mechanical memory element further includes a word line operatively connected to the movable gate; bit sense lines operatively connected to the source region and the drain region; and a bit pull up line operatively connected to the pull up electrode.
A mechanical memory transistor includes a substrate having formed thereon a source region and a drain region; a first pull down electrode positioned on the substrate; a second pull down electrode positioned on the substrate; and a movable gate having a first extension and a second extension, the movable gate having an anchor hinge located between the first and second extensions and located on the substrate between the second pull down electrode and the source and drain regions. The movable gate is in a first position when the first extension of the movable gate is in contact with the second pull down electrode and in a second position when the second extension of the movable gate is in contact with the first pull down electrode. The second extension of the movable gate, in conjunction with the source and drain regions and when the movable gate is in the second position, forms a transistor.
A mechanical memory element includes a transistor. The transistor has a substrate having formed thereon a source region and a drain region, a first pull down electrode positioned on the substrate, a second pull down electrode positioned on the substrate; and a movable gate having a first extension and a second extension, the movable gate having an anchor hinge located between the first and second extensions and located on the substrate between the second pull down electrode and the source and drain regions, the movable gate being in a first position when the first extension of the movable gate is in contact with the second pull down electrode, the movable gate being in a second position when the second extension of the movable gate is in contact with the first pull down electrode. The mechanical memory element further includes a word line operatively connected to the movable gate; bit sense lines operatively connected to the source and drain region; a first bit pull down line operatively connected to the first pull down electrode; and a second bit pull down line operatively connected to the second pull down electrode.
A mechanical memory element includes a transistor. The transistor has a substrate having formed thereon a first source region, a first drain region, a second source region, and a second drain region; a first pull down electrode positioned on the substrate; a second pull down electrode positioned on the substrate; and a movable gate having a first extension and a second extension, the movable gate having an anchor hinge located between the first and second extensions and located on the substrate between the second source and drain regions and the first source and drain regions. The movable gate is in a first position when the first extension of the movable gate is in contact with the first pull down electrode and in a second position when the second extension of the movable gate is in contact with the second pull down electrode. The first extension of the movable gate, in conjunction with the first source and drain regions and when the movable gate is in the first position, forms a first transistor. The mechanical memory element further includes a word line operatively connected to the movable gate; bit sense lines operatively connected to the second source and drain regions and the first source and drain regions; a first bit pull down line operatively connected to the first pull down electrode; and a second bit pull down line operatively connected to the second pull down electrode.
A mechanical memory transistor includes a substrate having formed thereon a first source region, a first drain region, a second source region, and a second drain region; a first pull down electrode positioned on the substrate; a second pull down electrode positioned on the substrate; and a movable gate having a first extension and a second extension, the movable gate having an anchor hinge located between the first and second extensions and located on the substrate between the second source and drain regions and the first source and drain regions. The movable gate is in a first position when the first extension of the movable gate is in contact with the first pull down electrode and in a second position when the second extension of the movable gate is in contact with the second pull down electrode. The first extension of the movable gate, in conjunction with the first source and drain regions and when the movable gate is in the first position, forms a first transistor. The second extension of the movable gate, in conjunction with the second source and drain regions and when the movable gate is in the second position, forms a second transistor.
A mechanical memory transistor includes a substrate having formed thereon a source region and a drain region; an oxide formed upon a portion of the source region and upon a portion of the drain region; a pull up electrode positioned above such that a gap is formed between the pull up electrode and the substrate; a pull down electrode located in the source and drain regions; and a movable gate having a first position and a second position, the movable gate being located in a gap above the pull up electrode and the substrate. The movable gate is in contact with the pull up electrode when the movable gate is in the first position and in contact with the oxide to form a gate region when the movable gate is in the second position. The movable gate, in conjunction with the source and drain regions and when the movable gate is in the second position, forms a transistor.
A mechanical memory element includes a transistor. The transistor has a substrate having formed thereon a source region and a drain region; an oxide formed upon a portion of the source region and upon a portion of the drain region; a pull up electrode positioned above such that a gap is formed between the pull up electrode and the substrate; a pull down electrode located in the source and drain regions; and a movable gate having a first position and a second position, the movable gate being located in a gap above the pull up electrode and the substrate, the movable gate being in contact with the pull up electrode when the movable gate is in the first position, the movable gate being in contact with the oxide to form a gate region when the movable gate is in the second position. The mechanical memory element further includes a word line operatively connected to the movable gate; bit sense lines operatively connected to the source region and the drain region; a bit pull up line operatively connected to the pull up electrode; and a bit pull down line operatively connected to the pull down electrode.